Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933355Ab3FRTgm (ORCPT ); Tue, 18 Jun 2013 15:36:42 -0400 Received: from fw01.core.ecsorl.com ([216.189.221.2]:42391 "EHLO hv11.core.ecsorl.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751301Ab3FRTgi (ORCPT ); Tue, 18 Jun 2013 15:36:38 -0400 X-Greylist: delayed 441 seconds by postgrey-1.27 at vger.kernel.org; Tue, 18 Jun 2013 15:36:38 EDT Date: Tue, 18 Jun 2013 15:33:34 -0400 From: liquidhorse@gmail.com To: netdev@vger.kernel.org Cc: zheng.x.li@oracle.com, fubar@us.ibm.com, andy@greyhouse.net, davem@davemloft.net, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH 3.4.y] bonding: rlb mode of bond should not alter ARP originating via bridge Message-ID: <20130618193334.GC29083@hv11.core.ecsorl.com> Reply-To: liquidhorse@gmail.com MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="SkvwRMAIpAhPCcCJ" Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4897 Lines: 132 --SkvwRMAIpAhPCcCJ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline From: zheng.li [ Upstream commit 567b871e503316b0927e54a3d7c86d50b722d955 ] Do not modify or load balance ARP packets passing through balance-alb mode (wherein the ARP did not originate locally, and arrived via a bridge). Modifying pass-through ARP replies causes an incorrect MAC address to be placed into the ARP packet, rendering peers unable to communicate with the actual destination from which the ARP reply originated. Load balancing pass-through ARP requests causes an entry to be created for the peer in the rlb table, and bond_alb_monitor will occasionally issue ARP updates to all peers in the table instrucing them as to which MAC address they should communicate with; this occurs when some event sets rx_ntt. In the bridged case, however, the MAC address used for the update would be the MAC of the slave, not the actual source MAC of the originating destination. This would render peers unable to communicate with the destinations beyond the bridge. Signed-off-by: Matthew O'Connor CC: Zheng Li Cc: Jay Vosburgh Cc: Andy Gospodarek Cc: "David S. Miller" Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org --SkvwRMAIpAhPCcCJ Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="balance-alb-3.4.patch" diff -uprN linux-3.4.28/drivers/net/bonding/bond_alb.c linux-3.4.28-patched/drivers/net/bonding/bond_alb.c --- linux-3.4.28/drivers/net/bonding/bond_alb.c 2013-01-27 23:51:45.000000000 -0500 +++ linux-3.4.28-patched/drivers/net/bonding/bond_alb.c 2013-01-30 15:37:25.121708311 -0500 @@ -704,6 +704,12 @@ static struct slave *rlb_arp_xmit(struct struct arp_pkt *arp = arp_pkt(skb); struct slave *tx_slave = NULL; + /* Don't modify or load balance ARPs that do not originate locally + * (e.g.,arrive via a bridge). + */ + if (!bond_slave_has_mac(bond, arp->mac_src)) + return NULL; + if (arp->op_code == htons(ARPOP_REPLY)) { /* the arp must be sent on the selected * rx channel diff -uprN linux-3.4.28/drivers/net/bonding/bonding.h linux-3.4.28-patched/drivers/net/bonding/bonding.h --- linux-3.4.28/drivers/net/bonding/bonding.h 2013-01-27 23:51:45.000000000 -0500 +++ linux-3.4.28-patched/drivers/net/bonding/bonding.h 2013-01-30 15:37:25.121708311 -0500 @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -450,6 +451,18 @@ static inline void bond_destroy_proc_dir } #endif +static inline struct slave *bond_slave_has_mac(struct bonding *bond, + const u8 *mac) +{ + int i = 0; + struct slave *tmp; + + bond_for_each_slave(bond, tmp, i) + if (ether_addr_equal_64bits(mac, tmp->dev->dev_addr)) + return tmp; + + return NULL; +} /* exported from bond_main.c */ extern int bond_net_id; diff -uprN linux-3.4.28/include/linux/etherdevice.h linux-3.4.28-patched/include/linux/etherdevice.h --- linux-3.4.28/include/linux/etherdevice.h 2013-01-27 23:51:45.000000000 -0500 +++ linux-3.4.28-patched/include/linux/etherdevice.h 2013-01-30 15:37:25.121708311 -0500 @@ -277,4 +277,37 @@ static inline unsigned long compare_ethe #endif } +/** + * ether_addr_equal_64bits - Compare two Ethernet addresses + * @addr1: Pointer to an array of 8 bytes + * @addr2: Pointer to an other array of 8 bytes + * + * Compare two Ethernet addresses, returns true if equal, false otherwise. + * + * The function doesn't need any conditional branches and possibly uses + * word memory accesses on CPU allowing cheap unaligned memory reads. + * arrays = { byte1, byte2, byte3, byte4, byte5, byte6, pad1, pad2 } + * + * Please note that alignment of addr1 & addr2 are only guaranteed to be 16 bits. + */ + +static inline bool ether_addr_equal_64bits(const u8 addr1[6+2], + const u8 addr2[6+2]) +{ +#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS + unsigned long fold = ((*(unsigned long *)addr1) ^ + (*(unsigned long *)addr2)); + + if (sizeof(fold) == 8) + return zap_last_2bytes(fold) == 0; + + fold |= zap_last_2bytes((*(unsigned long *)(addr1 + 4)) ^ + (*(unsigned long *)(addr2 + 4))); + return fold == 0; +#else + return ether_addr_equal(addr1, addr2); +#endif +} + + #endif /* _LINUX_ETHERDEVICE_H */ --SkvwRMAIpAhPCcCJ-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/